Lab Viso Limited 1 article published in JoVE Neuroscience Characterizing the Relationship Between Eye Movement Parameters and Cognitive Functions in Non-demented Parkinson's Disease Patients with Eye Tracking Oscar W.H. Wong1, Gabriel P.C. Fung2, Sandra Chan1 1Department of Psychiatry, The Chinese University of Hong Kong, 2Lab Viso Limited Here, we present a protocol to study the relationship between the eye movement parameters and cognitive functions in non-demented Parkinson's disease patients. The experiment used an eye tracker to measure the saccadic amplitude and fixation duration in a visual search task. The correlation with performance in multi-domain cognitive tasks was subsequently measured.